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Serpentine Belt – Fits MerCruiser 5.0L/5.7L/6.2L/7.4L (Replaces Mercury/MerCruiser 57-865615Q06)

Regular price $38.00
Shipping calculated at checkout.

Serpentine Belt – Fits MerCruiser 5.0L/5.7L/6.2L/7.4L (Replaces Mercury/MerCruiser 57-865615Q06) is backordered and will ship as soon as it is back in stock.


Worry-free returns

You may return most new, unopened items within 7 days of delivery for a full refund. We'll also pay the return shipping costs if the return is a result of our error (you received an incorrect or defective item, etc.).

You should expect to receive your refund within four weeks of giving your package to the return shipper, however, in many cases you will receive a refund more quickly. This time period includes the transit time for us to receive your return from the shipper (5 to 10 business days), the time it takes us to process your return once we receive it (3 to 5 business days), and the time it takes your bank to process our refund request (5 to 10 business days).

If you need to return an item, simply login to your account, view the order using the "Complete Orders" link under the My Account menu and click the Return Item(s) button. We'll notify you via e-mail of your refund once we've received and processed the returned item.

Delivery and Shipping

Free standard shipping on all orders under 1 KG

If you have any questions, feel free to email us at info@sierramarines.com, and we’ll get back to you within 20–36 hours.

Product Details

This replacement Serpentine Belt is designed for MerCruiser 5.0L, 5.7L, 6.2L, and 7.4L inboard and sterndrive engines manufactured between 1998 and 2004. It ensures reliable power transmission between critical engine components for both Alpha and Bravo applications.

This part is a direct replacement for Mercury/MerCruiser part numbers 57-865615Q06, 865615Q06, 57-865615006, 57-8638766, 57-8610491, and Sierra 18-15102.

  • Engineered for direct OEM replacement fit and function.
  • Constructed from high-strength rubber cords for durability.
  • Essential for powering accessories in Alpha and Bravo sterndrive systems.

Part Number Matrix

Use this matrix to confirm equivalent references across OEM and aftermarket.

Brand Part Number
Mercury/MerCruiser 57-865615Q06
Mercury/MerCruiser 865615Q06
Mercury/MerCruiser 57-865615006
Mercury/MerCruiser 57-8638766
Mercury/MerCruiser 57-8610491
Sierra 18-15102

Engine & Model Compatibility

Confirm your engine model/year in the table below.

Brand Model Stroke Years OEM Part No. Notes
MerCruiser 5.0L Alpha 4-Stroke 2000–2004 57-865615Q06 From serial OL619000 & OM600000
MerCruiser 5.0L Bravo 4-Stroke 2002–2004 57-865615Q06 From serial OM600000
MerCruiser 350 MAG Alpha 4-Stroke 2002–2004 57-865615Q06 From serial OM600000
MerCruiser 350 MAG Bravo 4-Stroke 2002–2004 57-865615Q06 From serial OM600000
MerCruiser 350 MAG MPI Alpha/Bravo EC 4-Stroke 2002–2004 57-865615Q06 From serial OM600000
MerCruiser 350 MAG MPI Horizon Alpha/Bravo EC 4-Stroke 2002–2004 57-865615Q06 From serial OM600000
MerCruiser 377 MAG MPI Bravo 4-Stroke 57-865615Q06
MerCruiser 377 MAG MPI Bravo EC 4-Stroke 57-865615Q06
MerCruiser 5.7L Alpha 4-Stroke 2000–2004 57-865615Q06 From serial OM600000
MerCruiser 5.7L Bravo 4-Stroke 2002–2004 57-865615Q06 From serial OM600000
MerCruiser MX 6.2L MPI 4-Stroke 2002–2004 57-865615Q06 From serial OM600000
MerCruiser MX 6.2L MPI Horizon 4-Stroke 2002–2004 57-865615Q06 From serial OM600000
MerCruiser 454 MAG MPI 4-Stroke 1998–2001 57-865615Q06 Serial OL010029-OM024999
MerCruiser 502 MAG MPI 4-Stroke 1998–2001 57-865615Q06 Serial OL017000-OM024999
MerCruiser 7.4L MPI 4-Stroke 1998–2001 57-865615Q06 Serial OL010003-OM024330

Technical Specs

Product Type
Serpentine Belt
Installation
Direct OEM replacement
Length
2,667 mm (105 inches)
Application
Power transmission between engine components
Material
High-strength rubber cords
Compatibility
Alpha and Bravo applications
OEM Part Number
57-865615Q06

What’s in the Box

  • 1 x Serpentine Belt (57-865615Q06)

Installation Notes

  1. Disconnect the boat's battery before beginning work.
  2. Locate the serpentine belt and identify the belt tensioner pulley.
  3. Use a correctly sized socket or wrench on the tensioner to release pressure on the belt.
  4. While holding the tensioner, carefully slide the old belt off the pulleys. Note the routing path.
  5. Route the new belt around the pulleys according to your engine's diagram.
  6. Ensure the belt's ribbed side is properly seated in the grooves of each pulley.
  7. Slowly release the tensioner to apply pressure to the new belt.
  8. Visually inspect the belt path one last time to confirm correct alignment.
  9. Reconnect the battery and start the engine, listening for unusual noises and verifying smooth operation.

Troubleshooting & FAQ

How do I know if this serpentine belt fits my engine?

Refer to the "Engine & Model Compatibility" section to verify your specific MerCruiser model and year. This belt is designed for the listed 5.0L, 5.7L, 6.2L, and 7.4L models within the specified serial number ranges. Cross-reference your existing part number with the numbers in the "Part Number Matrix" to ensure an exact match.

What are signs my serpentine belt is failing?

Common symptoms of a worn serpentine belt include loud squealing or chirping sounds from the engine, visible cracks, fraying, or glazing on the belt's surface, and accessory failure (e.g., alternator, power steering pump, or water pump).

How often should I replace my engine's serpentine belt?

As a general guideline, inspect your serpentine belt during routine maintenance and plan for replacement every 500-1000 hours of use or every few years, depending on operating conditions and manufacturer recommendations. Belts in marine environments are exposed to harsh conditions that can accelerate wear.

Can I install this belt myself?

Installation is straightforward for individuals with mechanical experience and the proper tools. However, due to the importance of correct belt routing and tensioning for engine safety and performance, professional installation is recommended.

OEM vs. Aftermarket?

This listing is an aftermarket replacement (not OEM). Built to OEM-level specifications with comparable materials. Manufactured in an ISO 9002 facility, batch-inspected for consistency.

Shipping speed & cost

We ship worldwide quickly—typical transit 5–15 days. Standard shipping is free; expedited options appear at checkout where available.

Warranty & returns

Covered by a 1-year warranty against manufacturing defects under normal use. If issues arise, contact support with your order details. Returns are accepted within our standard window (unused & in original condition). See our policy page or reach out for instructions.

Safety & Important Info

  • Verify images/specifications vs your original part. If anything differs—even if your model appears compatible—do not purchase.
  • This is an aftermarket replacement, not an OEM component.
  • Professional installation is recommended for safety and performance.

About Sea Sierra

  • Pro-Grade Standards — We supply marine parts engineered to OEM-level tolerances and tested for real-world conditions.
  • Fast Global Fulfillment — Free standard delivery to most regions in 5–15 days.
  • Manufacturer-Direct Value — Fair pricing without compromising on materials or QC.

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